Aircraft engines in the military sector regularly have a thrust deflecting device for increasing a flight maneuverability, which reverses a thrust stream in the pitch direction and yaw direction. An exemplary thrust deflecting device is shown in U.S. Pat. No. 4,978,071 A. This thrust deflecting device has a housing for the transition from a round outlet cross section to a rectangular outlet cross section. To deflect the thrust stream in the pitch direction and the yaw direction, the thrust deflecting device has two pairs of side flaps situated orthogonally with respect to each other. Similar thrust deflecting devices are illustrated in U.S. Pat. No. 4,836,451 A, U.S. Pat. No. 5,687,907 A and U.S. Pat. No. 4,848,664 A, in which a thrust stream is also deflected in the pitch direction or the yaw direction with the aid of lateral side flap pairs situated orthogonally with respect to each other. A device for controlling the yaw of a nozzle having a rectangular outlet cross section is furthermore known from DE 10 2006 031 625 A1. A thrust deflecting device is known from U.S. Pat. No. 5,769,317 A, in which a deflection of a thrust stream in the pitch direction takes place by pivoting a nozzle around a transverse axis, and a deflection of the thrust stream in the yaw direction takes place with the aid of a vertical flap pair extending downstream from the nozzle. The disadvantage of these known thrust deflecting devices is a complex mechanical design for activating and moving the flap pairs and the nozzle.